Horton

Re: BUG #15964: vacuumdb.c:187:10: error: use of undeclared identifier 'FD_SETSIZE'

Alvaro Herrera <alvherre@2ndquadrant.com>

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From: Alvaro Herrera <alvherre@2ndquadrant.com>
To: Michael Paquier <michael@paquier.xyz>
Cc: Andres Freund <andres@anarazel.de>, Tom Lane <tgl@sss.pgh.pa.us>, Dilip Kumar <dilipbalaut@gmail.com>, jungleboogie0@gmail.com, pgsql-bugs@lists.postgresql.org
Date: 2019-08-21T14:16:36Z
Lists: pgsql-bugs 
On 2019-Aug-21, Michael Paquier wrote:

> On Wed, Aug 21, 2019 at 09:49:54AM -0400, Alvaro Herrera wrote:

> > Well, it's a user-facing error, so I'd rather make it user-friendly.
> > It doesn't seem difficult, or unreliable enough not to try.
> 
> Still, in this case, because of the nature of FD_SETSIZE the hint may
> finish by being wrong, no?  I am not sure that it is worth going this
> way.

Theoretically it is possible that we give a wrong hint, but I think it's
hardly a practical reality.  I'd rather give the hint and tell the user
what a reasonable parameter might be.  If they run under a different
environment (I dunno, they use shell invocation line with other
redirections I guess), then they might get a different hint next time.
So what?

I guess the other possibility is that there exists an operating system
that returns file descriptors higher than its FD_SETSIZE, when some fds
below FD_SETSIZE are still available.  Doesn't seem realistic.

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services

Commits

  1. Fix error handling of vacuumdb when running out of fds

  2. Fix error handling of vacuumdb and reindexdb when running out of fds

  3. Fix compilation failure of vacuumdb and reindexdb with OpenBSD

  4. Improve Assert output

  5. Refactor parallelization processing code in src/bin/scripts/

  6. vacuumdb: enable parallel mode